For more than a decade, we have been studying how nerve and other cells repair themselves after injury. Repair processes and underlying cellular mechanisms have not been studied extensively and there is much to learn about fundamental mechanisms. Neural repair is a topic of current interest to neurobiologists, and an understanding of repair mechanisms is essential for developing therapeutic strategies which can facilitate repair of severed human nerves. Previously we used injury current measures to determine the time course of sealing in severed giant axons of squid, crayfish and earthworm. We now wish to obtain characterization on a microscopic level using the patch clamp technique on single cells. During this visit to the MBL we have used the tissue culture facilities of BRC to culture GH3 (rat pituitary) cells to provide single cells for our studies of how vesicles, induced after injury, repair plasmalemma damage. In particular we have been characterizing microscopic electrical changes associated with seal formation.